Field
The present invention relates to a touch display apparatus. More particularly, the present invention relates to a touch display apparatus having a reduced thickness with high alignment accuracy between a touch panel and a display panel and a method of fabricating thereof.
Description of the Related Art
Conventional input devices, such as a keyboard or mouse, have been gradually replaced by touch devices for a convenient user interface. The touch device is capable of being mounted on various flat display apparatuses such that the touch and display functions can be simultaneously implemented on a touch display apparatus. Typically, the touch panel is mounted on a liquid crystal panel or an OLED display panel, for apparatuses such as tablets or smart phones.
In the conventional method of fabricating a touch display apparatus, the display panel and the touch panel are fabricated individually and then adhere to each other. Thus, each of the display panel and the touch panel needs an upper substrate and a lower substrate. These substrates are usually glass substrates having the disadvantages of being thick and heavy. The substrates of the display panel may be thinned by a thinning process after they are assembled to each other. However, the substrates can't be further thinned after the display panel and touch panel are assembled, and therefore the thickness of the touch display apparatus cannot be further reduced. In addition, both the upper and the lower substrates of the display panel would have an alignment mark, and the assembling of the upper and the lower substrates of the display panel by aligning the alignment marks has an alignment tolerance of less than about 5 μm. However, the dimensions of active areas of the display panel and the touch panel are different. The alignment marks used to align the upper and lower substrates of the display panel and the alignment marks used to align the upper and lower substrates of the touch panel are not overlapped when assembling the display panel and the touch panel. Thus, an additional alignment mark for aligning the touch panel to the display panel is needed, and the assembling of the display panel and the touch panel can only have an alignment tolerance of between around 70 and 80 μm. Moreover, the yield would be significantly lowered and the cost would be increased when trying to reduce the alignment tolerance of the assembling of the display panel and the touch panel. Thus, the conventional method is not suitable for fabricating a touch display apparatus having a high resolution display panel, in particular a 3D touch display apparatus.
Therefore, a touch display device capable of addressing the above issues and a method of fabricating thereof are needed.